AD converter evaluation apparatus

Abstract

An AD converter evaluation apparatus evaluates an AD converter, which includes a first programmable power supply, a second programmable power supply, an attenuator circuit, an addition circuit, and a digital multimeter. The first and second programmable power supplies sets a first and second voltages. The attenuator circuit attenuates the first voltage of the second programmable power supply. The addition circuit adds the first voltage of the first programmable power supply and the attenuated voltage of the attenuator circuit. The digital multimeter measures the first voltage of the first programmable power supply and the second voltage of the second programmable power supply. Output voltage of the addition circuit is input to the AD converter.

What is claimed is:  
     
       1. An AD converter evaluation apparatus for evaluating an AD converter, comprising: 
       a first programmable power supply for applying a first voltage;  
       a second programmable power supply for applying a second voltage;  
       an attenuator circuit for attenuating the second voltage output from the second programmable power supply to generate a third voltage;  
       an addition circuit for adding the third voltage of the attenuator circuit to the first voltage output from the first programmable power supply to generate a fourth voltage for input to the AD converter; and  
       a digital multimeter for measuring the first voltage of the first programmable power supply and the second voltage of the second programmable power supply.  
     
     
       2. The AD converter evaluation apparatus as claimed in  claim 1 , further comprising: 
       a computer; and  
       a controller connected to the computer and connected through an interface section to the digital multimeter and the AD converter, the controller for controlling the AD converter.  
     
     
       3. The AD converter evaluation apparatus as claimed in  claim 2 , wherein the digital multimeter measures the fourth voltage of the addition circuit and outputs an actual measured voltage of the fourth voltage to the computer. 
     
     
       4. The AD converter evaluating apparatus as claimed in  claim 3 , wherein the computer compares the actual measured voltage with an expected voltage of the fourth voltage programmed in the computer in advance to calculate a difference between the actual measured voltage and the expected voltage. 
     
     
       5. The AD converter evaluating apparatus as claimed in  claim 4 , wherein the computer resets the first and second voltages of the first and second programmable power supplies, thereby to cancel out an error component thereof. 
     
     
       6. The AD converter evaluating apparatus as claimed in  claim 5 , wherein the reset first and second voltages of the first and second programmable power supplies are for input to the AD converter; and 
       the controller transmits an AD converter conversion start signal to start conversion operation of the AD converter.  
     
     
       7. The AD converter evaluating apparatus as claimed in  claim 1  wherein, during operation, the attenuator circuit attenuates the second voltage by a plurality of orders of magnitude.